It is not official, you have to ask for it via pn.
Here: http://www.hardwareluxx.de/community/members/doktor-asus--123843/
Or you can go here:
0502 Bios
Running this now interestingly enough at 4.6ghz all the same settings i had in 0501 I am getting a slightly lower completion time and higher gflops in linx?!?